<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <title></title>
    <script>
    let arr=[12,5,88,37,21,91,17,24];

    let sum=0;
    arr.forEach(item=>{
      sum+=item;
    });

    alert(sum);
    </script>
  </head>
  <body>

  </body>
</html>
